Mercurial > hg > smallbox
diff util/SMALL_ssim_index.m @ 119:5356a6e13a25 sup_163_ssim_IMG_T_dependeny
New version of ssim index - IMP toolbox dependencies removed
| author | Ivan Damnjanovic lnx <ivan.damnjanovic@eecs.qmul.ac.uk> |
|---|---|
| date | Tue, 24 May 2011 16:16:36 +0100 |
| parents | |
| children | 8e660fd14774 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/util/SMALL_ssim_index.m Tue May 24 16:16:36 2011 +0100 @@ -0,0 +1,238 @@ +function [mssim, ssim_map] = SMALL_ssim_index(img1, img2, K, window, L) + +%======================================================================== +%SSIM Index, Version 1.0 +%Copyright(c) 2003 Zhou Wang +%All Rights Reserved. +% +%The author is with Howard Hughes Medical Institute, and Laboratory +%for Computational Vision at Center for Neural Science and Courant +%Institute of Mathematical Sciences, New York University. +% +%---------------------------------------------------------------------- +%Permission to use, copy, or modify this software and its documentation +%for educational and research purposes only and without fee is hereby +%granted, provided that this copyright notice and the original authors' +%names appear on all copies and supporting documentation. This program +%shall not be used, rewritten, or adapted as the basis of a commercial +%software or hardware product without first obtaining permission of the +%authors. The authors make no representations about the suitability of +%this software for any purpose. It is provided "as is" without express +%or implied warranty. +%---------------------------------------------------------------------- +% +%This is an implementation of the algorithm for calculating the +%Structural SIMilarity (SSIM) index between two images. Please refer +%to the following paper: +% +%Z. Wang, A. C. Bovik, H. R. Sheikh, and E. P. Simoncelli, "Image +%quality assessment: From error measurement to structural similarity" +%IEEE Transactios on Image Processing, vol. 13, no. 1, Jan. 2004. +% +%Kindly report any suggestions or corrections to zhouwang@ieee.org +% +%---------------------------------------------------------------------- +% +%Input : (1) img1: the first image being compared +% (2) img2: the second image being compared +% (3) K: constants in the SSIM index formula (see the above +% reference). defualt value: K = [0.01 0.03] +% (4) window: local window for statistics (see the above +% reference). default widnow is Gaussian given by +% window = fspecial('gaussian', 11, 1.5); +% (5) L: dynamic range of the images. default: L = 255 +% +%Output: (1) mssim: the mean SSIM index value between 2 images. +% If one of the images being compared is regarded as +% perfect quality, then mssim can be considered as the +% quality measure of the other image. +% If img1 = img2, then mssim = 1. +% (2) ssim_map: the SSIM index map of the test image. The map +% has a smaller size than the input images. The actual size: +% size(img1) - size(window) + 1. +% +%Default Usage: +% Given 2 test images img1 and img2, whose dynamic range is 0-255 +% +% [mssim ssim_map] = ssim_index(img1, img2); +% +%Advanced Usage: +% User defined parameters. For example +% +% K = [0.05 0.05]; +% window = ones(8); +% L = 100; +% [mssim ssim_map] = ssim_index(img1, img2, K, window, L); +% +%See the results: +% +% mssim %Gives the mssim value +% imshow(max(0, ssim_map).^4) %Shows the SSIM index map +% + +% Removed dependency on Image Processing Toolbox - +% Centre for Digital Music, Queen Mary, University of London. +% This file copyright 2011 Ivan Damnjanovic. +%======================================================================== + + +if (nargin < 2 || nargin > 5) + ssim_index = -Inf; + ssim_map = -Inf; + return; +end + +if (size(img1) ~= size(img2)) + ssim_index = -Inf; + ssim_map = -Inf; + return; +end + +[M N] = size(img1); + +if (nargin == 2) + if ((M < 11) || (N < 11)) + ssim_index = -Inf; + ssim_map = -Inf; + return + end +% window = fspecial('gaussian', 11, 1.5); % +% +% Image Processing toolboxdependency +% - fspecial function is from IMP toolbox +% 2 - ways to do +% a) +% [wx,wy] = meshgrid(-5:5, -5:5); +% window = exp(-(wx.*wx + wy.*wy)/4.5); +% window = window/sum(window(:)); +% b) + window = [1.05756559815326e-06,7.81441153305360e-06,3.70224770827489e-05,0.000112464355116679,0.000219050652866017,0.000273561160085806,0.000219050652866017,0.000112464355116679,3.70224770827489e-05,7.81441153305360e-06,1.05756559815326e-06;... + 7.81441153305360e-06,5.77411251978637e-05,0.000273561160085806,0.000831005429087199,0.00161857756253439,0.00202135875836257,0.00161857756253439,0.000831005429087199,0.000273561160085806,5.77411251978637e-05,7.81441153305360e-06;... + 3.70224770827489e-05,0.000273561160085806,0.00129605559384320,0.00393706926284679,0.00766836382523672,0.00957662749024029,0.00766836382523672,0.00393706926284679,0.00129605559384320,0.000273561160085806,3.70224770827489e-05;... + 0.000112464355116679,0.000831005429087199,0.00393706926284679,0.0119597604100370,0.0232944324734871,0.0290912256485504,0.0232944324734871,0.0119597604100370,0.00393706926284679,0.000831005429087199,0.000112464355116679;... + 0.000219050652866017,0.00161857756253439,0.00766836382523672,0.0232944324734871,0.0453713590956603,0.0566619704916846,0.0453713590956603,0.0232944324734871,0.00766836382523672,0.00161857756253439,0.000219050652866017;... + 0.000273561160085806,0.00202135875836257,0.00957662749024029,0.0290912256485504,0.0566619704916846,0.0707622377639470,0.0566619704916846,0.0290912256485504,0.00957662749024029,0.00202135875836257,0.000273561160085806;... + 0.000219050652866017,0.00161857756253439,0.00766836382523672,0.0232944324734871,0.0453713590956603,0.0566619704916846,0.0453713590956603,0.0232944324734871,0.00766836382523672,0.00161857756253439,0.000219050652866017;... + 0.000112464355116679,0.000831005429087199,0.00393706926284679,0.0119597604100370,0.0232944324734871,0.0290912256485504,0.0232944324734871,0.0119597604100370,0.00393706926284679,0.000831005429087199,0.000112464355116679;... + 3.70224770827489e-05,0.000273561160085806,0.00129605559384320,0.00393706926284679,0.00766836382523672,0.00957662749024029,0.00766836382523672,0.00393706926284679,0.00129605559384320,0.000273561160085806,3.70224770827489e-05;... + 7.81441153305360e-06,5.77411251978637e-05,0.000273561160085806,0.000831005429087199,0.00161857756253439,0.00202135875836257,0.00161857756253439,0.000831005429087199,0.000273561160085806,5.77411251978637e-05,7.81441153305360e-06;... + 1.05756559815326e-06,7.81441153305360e-06,3.70224770827489e-05,0.000112464355116679,0.000219050652866017,0.000273561160085806,0.000219050652866017,0.000112464355116679,3.70224770827489e-05,7.81441153305360e-06,1.05756559815326e-06]; + K(1) = 0.01; % default settings + K(2) = 0.03; % + L = 255; % +end + +if (nargin == 3) + if ((M < 11) || (N < 11)) + ssim_index = -Inf; + ssim_map = -Inf; + return + end +% window = fspecial('gaussian', 11, 1.5); % +% +% Image Processing toolboxdependency +% - fspecial function is from IMP toolbox +% 2 - ways to do +% a) +% [wx,wy] = meshgrid(-5:5, -5:5); +% window = exp(-(wx.*wx + wy.*wy)/4.5); +% window = window/sum(window(:)); +% b) + window = [1.05756559815326e-06,7.81441153305360e-06,3.70224770827489e-05,0.000112464355116679,0.000219050652866017,0.000273561160085806,0.000219050652866017,0.000112464355116679,3.70224770827489e-05,7.81441153305360e-06,1.05756559815326e-06;... + 7.81441153305360e-06,5.77411251978637e-05,0.000273561160085806,0.000831005429087199,0.00161857756253439,0.00202135875836257,0.00161857756253439,0.000831005429087199,0.000273561160085806,5.77411251978637e-05,7.81441153305360e-06;... + 3.70224770827489e-05,0.000273561160085806,0.00129605559384320,0.00393706926284679,0.00766836382523672,0.00957662749024029,0.00766836382523672,0.00393706926284679,0.00129605559384320,0.000273561160085806,3.70224770827489e-05;... + 0.000112464355116679,0.000831005429087199,0.00393706926284679,0.0119597604100370,0.0232944324734871,0.0290912256485504,0.0232944324734871,0.0119597604100370,0.00393706926284679,0.000831005429087199,0.000112464355116679;... + 0.000219050652866017,0.00161857756253439,0.00766836382523672,0.0232944324734871,0.0453713590956603,0.0566619704916846,0.0453713590956603,0.0232944324734871,0.00766836382523672,0.00161857756253439,0.000219050652866017;... + 0.000273561160085806,0.00202135875836257,0.00957662749024029,0.0290912256485504,0.0566619704916846,0.0707622377639470,0.0566619704916846,0.0290912256485504,0.00957662749024029,0.00202135875836257,0.000273561160085806;... + 0.000219050652866017,0.00161857756253439,0.00766836382523672,0.0232944324734871,0.0453713590956603,0.0566619704916846,0.0453713590956603,0.0232944324734871,0.00766836382523672,0.00161857756253439,0.000219050652866017;... + 0.000112464355116679,0.000831005429087199,0.00393706926284679,0.0119597604100370,0.0232944324734871,0.0290912256485504,0.0232944324734871,0.0119597604100370,0.00393706926284679,0.000831005429087199,0.000112464355116679;... + 3.70224770827489e-05,0.000273561160085806,0.00129605559384320,0.00393706926284679,0.00766836382523672,0.00957662749024029,0.00766836382523672,0.00393706926284679,0.00129605559384320,0.000273561160085806,3.70224770827489e-05;... + 7.81441153305360e-06,5.77411251978637e-05,0.000273561160085806,0.000831005429087199,0.00161857756253439,0.00202135875836257,0.00161857756253439,0.000831005429087199,0.000273561160085806,5.77411251978637e-05,7.81441153305360e-06;... + 1.05756559815326e-06,7.81441153305360e-06,3.70224770827489e-05,0.000112464355116679,0.000219050652866017,0.000273561160085806,0.000219050652866017,0.000112464355116679,3.70224770827489e-05,7.81441153305360e-06,1.05756559815326e-06]; + L = 255; + if (length(K) == 2) + if (K(1) < 0 || K(2) < 0) + ssim_index = -Inf; + ssim_map = -Inf; + return; + end + else + ssim_index = -Inf; + ssim_map = -Inf; + return; + end +end + +if (nargin == 4) + [H W] = size(window); + if ((H*W) < 4 || (H > M) || (W > N)) + ssim_index = -Inf; + ssim_map = -Inf; + return + end + L = 255; + if (length(K) == 2) + if (K(1) < 0 || K(2) < 0) + ssim_index = -Inf; + ssim_map = -Inf; + return; + end + else + ssim_index = -Inf; + ssim_map = -Inf; + return; + end +end + +if (nargin == 5) + [H W] = size(window); + if ((H*W) < 4 || (H > M) || (W > N)) + ssim_index = -Inf; + ssim_map = -Inf; + return + end + if (length(K) == 2) + if (K(1) < 0 || K(2) < 0) + ssim_index = -Inf; + ssim_map = -Inf; + return; + end + else + ssim_index = -Inf; + ssim_map = -Inf; + return; + end +end + +C1 = (K(1)*L)^2; +C2 = (K(2)*L)^2; +window = window/sum(sum(window)); +img1 = double(img1); +img2 = double(img2); + +mu1 = filter2(window, img1, 'valid'); +mu2 = filter2(window, img2, 'valid'); +mu1_sq = mu1.*mu1; +mu2_sq = mu2.*mu2; +mu1_mu2 = mu1.*mu2; +sigma1_sq = filter2(window, img1.*img1, 'valid') - mu1_sq; +sigma2_sq = filter2(window, img2.*img2, 'valid') - mu2_sq; +sigma12 = filter2(window, img1.*img2, 'valid') - mu1_mu2; + +if (C1 > 0 & C2 > 0) + ssim_map = ((2*mu1_mu2 + C1).*(2*sigma12 + C2))./((mu1_sq + mu2_sq + C1).*(sigma1_sq + sigma2_sq + C2)); +else + numerator1 = 2*mu1_mu2 + C1; + numerator2 = 2*sigma12 + C2; + denominator1 = mu1_sq + mu2_sq + C1; + denominator2 = sigma1_sq + sigma2_sq + C2; + ssim_map = ones(size(mu1)); + index = (denominator1.*denominator2 > 0); + ssim_map(index) = (numerator1(index).*numerator2(index))./(denominator1(index).*denominator2(index)); + index = (denominator1 ~= 0) & (denominator2 == 0); + ssim_map(index) = numerator1(index)./denominator1(index); +end + +mssim = sum(ssim_map(:), [], 'double')/numel(ssim_map); + +return \ No newline at end of file